The student activist, who helped lead the months-long movement in 2014 demanding full democracy appeared in court on Thursday for a pre-trial hearing, which was adjourned for 45 days.
Wong is among 20 defendants charged with contempt of court after refusing to obey a court order to clear the protest zone in December 2014.
The demonstrators, who had demanded democratic elections for Hong Kong's chief executive, were arrested last year.
"I choose to plead guilty in this case to show, as an organiser of civil disobedience, I am willing to bear legal responsibility," the 20-year-old Wong said outside the High Court, flanked by a few supporters.
"Although there's a chance I might be put in jail, I have no regrets."
In written statements to the court, Wong and several respondents, including another student leader Lester Shum, "admitted liability", rather than explicitly pleading guilty, as is the case in a civil, rather than criminal, lawsuit.
Wong will now find out his fate at the end of the 45-day hearing of the trial in August. The judge will call in 33 more witnesses.
Al Jazeera's Sarah Clarke, reporting from outside the court, said: "We had expected a quick turnaround in the next day or two on the sentences for those pleading guilty, but the judge has announced that he wants to hear all of the cases."
One of the student politicians has already been sentenced to three months of jail time for the same charge after the judge said he showed no remorse.
"Wong said he's proud to be standing up for democracy, which means serving time behind bars and that's fine by him," said Al Jazeera's Clarke.
Wong has previously been found guilty of unlawful assembly on a charge also related to the 2014 protests, but he avoided jail time.